Insights into the Exfoliation Process of V2O5· nH2O Nanosheet Formation Using Real-Time 51V NMR
Artikel i vetenskaplig tidskrift, 2019

Copyright © 2019 American Chemical Society. Nanostructured hydrated vanadium oxides (V2O5·nH2O) are actively being researched for applications in energy storage, catalysis, and gas sensors. Recently, a one-step exfoliation technique for fabricating V2O5·nH2O nanosheets in aqueous media was reported; however, the underlying mechanism of exfoliation has been challenging to study. Herein, we followed the synthesis of V2O5·nH2O nanosheets from the V2O5 and VO2 precursors in real time using solution- and solid-state 51V NMR. Solution-state 51V NMR showed that the aqueous solution contained mostly the decavanadate anion [H2V10O28]4- and the hydrated dioxovanadate cation [VO2·4H2O]+, and during the exfoliation process, decavanadate was formed, while the amount of [VO2·4H2O]+ remained constant. The conversion of the solid precursor V2O5, which was monitored with solid-state 51V NMR, was initiated when VO2 was in its monoclinic forms. The dried V2O5·nH2O nanosheets were weakly paramagnetic because of a minor content of isolated V4+. Its solid-state 51V signal was less than 20% of V2O5 and arose from diamagnetic V4+ or V5+.This study demonstrates the use of real-time NMR techniques as a powerful analysis tool for the exfoliation of bulk materials into nanosheets. A deeper understanding of this process will pave the way to tailor these important materials. ©

Författare

Ahmed S. Etman

Stockholms universitet

Linköpings universitet

Alexandria University

Andrew J. Pell

Stockholms universitet

P Svedlindh

Uppsala universitet

Niklas Hedin

Stockholms universitet

Xiaodong Zou

Stockholms universitet

Junliang Sun

Stockholms universitet

Beijing University of Technology

Diana Bernin

Stockholms universitet

Chalmers, Kemi och kemiteknik, Kemiteknik, Kemisk apparatteknik

ACS Omega

24701343 (eISSN)

Vol. 4 6 10899-10905

Ämneskategorier

Fysikalisk kemi

Materialkemi

Annan kemiteknik

DOI

10.1021/acsomega.9b00727

Mer information

Senast uppdaterat

2019-07-12